science exam 3 hard
Terms in this set (67)
spring tides occur
when the sun, moon, and Earth line up
the pull of gravity on the surface of the moon is _____ of that of Earth
the day in March (the 21st) when sun is overhead at noon at the Equator is called the?
when the moon is in Earth's ___ you see a total lunar eclipse
a lunar eclipse only occurs at a __ moon
the heliocentric system gained support when Galileo observed ?
venus goes through phases similar to those of Earth's moon
the solar system formed form
gaint cloud of gas and dust
small asteroid like bodies that became the building blocks for the planets are called
the sun produces energy by
the solar wind is a stream of electrically charged particles that extend outward from the suns?
what do the four outer planets have in common
they are much larger than Earth and are made mainly of hydrogen and heluim
mar's atmosphere is mostly ?
the number of sunspots on the sun varies over a period of about _ years
most comets are found in the
the sun's surface layer is the
the HR diagram shows that main sequence stars?
increase in brightness as they increase in temperature
characteristics to classify stars include
size, brightness, and temperature
a star is born when
nuclear fusion starts
what is a major difference between elliptical galaxies and spiral galaxies
elliptical galaxies have almost no gas or dust between the stars
eclipsing binary stars can sometimes be indentified because
they become dimmer at regular intervals
from the cosmic background radiation, scientists can infer that, just after the big bang, the universe must have been
humans first landed on the moon in
the spacecraft that carried most of the parts for the ISS into orbit is called
astronauts orbitng Earth experience microgravity because?
gravity's force is balanced by their forward velocity
the main purpose of a space station is to
carry out scientific expriments in space
who was the 1st human in space
who was the 1st human on the moon
the 1st american to orbit earth
who was an early american rocket scientist
name two private companies that are currently working to send rockets into space
1. virgin galatic 2. space x 3. blue orgin
magma that forces its way into other rocks and hardens is called a
a petrified fossil forms when
minerals replace all or part of an organism
the earliest forms of life appeared during
what was the cambrian explosion
when a large number of differnt organisms evolved
the mesozoic era is often called the ?
age of reptiles
scientists use radioactive dating to ?
determine the absolute ages of rocks
at 3,476 kilometers, the moon's diameter is slightly less than the distance across ?
what tool can help you find constellations in the night sky
narrow band in the sky thru which planets appear to move
earths __________ causes seasonal changes in the constellations you can observe
orbit around the sun
stars are made up of ?
heluim and hydrogen
what is the brightest object in the sky
when the noon sun is directly overhead at the equator
when the sun is farthest north or south of the equator
Earth is closest to the sun when it is summer in what hemisphere?
how does distance affect the strength of the force of gravity
gravity decreases to _____ of its original value if the distance between two objects doubles
Earth's gravity pulls the moon _____
a person standing in the moon's prenumbra would see a ____eclipse
a person standing in the moon's umbra would see a _____ eclispe
on day on the moon is the same length as one _____ on earth
changes in position of Earth, the moon , and the sun affect the ________ of high tides during a month
what does the fossil record reveal about the evolution of life on Earth
older rocks contain simpler organisms than present organisms
amphibians evolved from
during what period did plants and insects become abudant
in what period did mammals exist
galileo discovered how many moons around Jupiter
about 3/4 of the sun's mass is ?
the thick clouds on Venus are made up of
sulfric acid droplets
which planet's axis has a tilt of 90 degress
which one of Saturn's moons may support life
galaxies are held together by
what are two pieces of evidence that support the big bang theory
cosmic background radiation and hubble's law
what supports the presence of dark energy
the speed at which the galaxies are moving apart
observation satellites collect data by
most communication satellites are
in a geostationary orbit
because space has almost no air, it is nearly a